Resistance to amphotericin B associated with defective sterol delta 8-->7 isomerase in a Cryptococcus neoformans strain from an AIDS patient

FEMS Microbiol Lett. 1994 Sep 15;122(1-2):39-42. doi: 10.1111/j.1574-6968.1994.tb07140.x.


Two Cryptococcus neoformans strains isolated from an AIDS patient were investigated, a pretreatment isolate (CN1) and a second isolate (CN3) following failure of fluconazole and amphotericin B treatment. No difference in fluconazole sensitivity, but relative resistance to amphotericin B was observed for CN3. The sterol composition of CN3 indicated a defect in sterol delta 8-->7 isomerase in this strain and depletion of ergosterol, the major sterol of the CN1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acquired Immunodeficiency Syndrome / microbiology*
  • Amphotericin B / pharmacology*
  • Cryptococcus neoformans / drug effects*
  • Cryptococcus neoformans / enzymology*
  • Drug Resistance, Microbial / genetics
  • Humans
  • Microbial Sensitivity Tests
  • Mutation / genetics
  • Steroid Isomerases / genetics*


  • Amphotericin B
  • Steroid Isomerases